柠檬酸还原性体系浸出废旧锂电池中有价金属

Leaching of valuable metals from spent lithium-ion batteries by citric acid reducing system

随着电动汽车和便携式电子产品用量的不断增长以及对可持续资源管理需求的提升,废旧锂离子电池的回收变得越来越重要。以废旧三元锂电池中的混合电极活性材料为研究对象,考察了硫酸-柠檬酸体系下不同反应参数对有价金属Li、Ni、Co和Mn浸出率的影响。结果表明,在1.0 mol/L硫酸为浸出剂、10%(质量分数)柠檬酸为还原剂的混酸体系下,固液比为40 g/L、浸出温度为80℃、浸出时间为120 min时,Co、Ni、Li、Mn的最大浸出率分别为98.52%、98.67%、99.73%、98.48%。在此基础上,通过X射线衍射(XRD)、傅里叶变换红外光谱(FT-IR)、扫描电镜-能谱(SEM-EDS)和电子探针(EMPA)等表征手段对硫酸-柠檬酸协同浸出机理进行了探析。该研究为采用还原性有机酸从废旧三元锂离子电池混合电极材料中绿色、安全、高效回收有价金属提供了技术方案。

The recycling of spent lithium-ion batteries has become more and more important with the increasing use of electric vehicles and portable electronics,and the demand for sustainable resource management.The effects of various reaction parameters on leaching efficiencies of valuable metals Li,Ni,Co,and Mn in the sulfuric acid-citric acid system were investigated with the mixed electrode active materials of spent ternary lithium-ion batteries as the research object.The results show that under the mixed acid system with 1.0 mol/L sulfuric acid as leaching agent and 10%(mass fraction)citric acid as reducing agent,the maximum leaching efficiencies of Co,Ni,Li and Mn are 98.52%,98.67%,99.73%and 98.48%,respectively,when the solid-liquid ratio is 40 g/L,the leaching temperature is 80℃and the leaching time is 120 min.On this basis,X-ray diffraction(XRD),Fourier-transform infrared spectroscopy(FT-IR),scanning spectroscopy(SEM-EDS),and electron microprobe analysis(EMPA)were applied to gain insight into the mechanism of sulfuric acid-citric acid collaborative leaching.This study provides a green,safe,and efficient technical solution for recovering valuable metals from mixed electrode materials in spent ternary lithium-ion batteries.